Social impairment is a prominent feature of schizotypal[unreadable] personality disorder (SPD) and is often manifested in subjects by having few friends and long periods of[unreadable] unemployment. It is hypothesized that a combination of input and output emotional processing deficits[unreadable] explains the social and occupational failure of SPD subjects. In this R21 resubmission application[unreadable] simple sensory input and motor output of emotional faces and prosody will be compared in SPD and[unreadable] control subjects. The main hypothesis is that DSM-IV diagnosed SPD subjects, compared with control[unreadable] subjects, will exhibit deficits in information processing essential to social reciprocity (i.e., sensory[unreadable] processing of facial emotions and emotional prosody), and also deficits in the motoric output of signals[unreadable] related to social reciprocity (i.e., facial expressions and voice inflection), which are needed to convey[unreadable] social and emotional meaning. These four aspects of social reciprocity will be studied using behavioral[unreadable] measures, a computer-derived emotional expression task, videotapes, pitch analysis (measure of[unreadable] prosody), as well as by structural and functional MRI (fMRI). To achieve these aims, 24 neurolepticnaive[unreadable] SPD subjects age, gender, parental socio- economically matched to 24 comparison subjects, will[unreadable] be recruited from the community. A further rationale for studying SPD subjects is they are not psychotic[unreadable] and have not received neuroleptic medications. Yet SPD subjects share the same genetic diathesis as[unreadable] schizophrenia, and thus offer a unique opportunity to examine the behavior and the functional[unreadable] neuroanatomy of schizophrenia spectrum disorders, without multiple researches confounds such as[unreadable] medication effects and stress due to serious mental illness. Relevance to NIMH's mission:[unreadable] Understanding fundamental abnormalities in social reciprocity in SPD could have a significant impact[unreadable] on our conceptualization of these deficits in schizophrenia, which, in turn, might stimulate further social[unreadable] rehabilitation research.